The invention pertains to methods of forming material adjacent electrical components and to methods of forming material between conductive electrical components. The invention further pertains to insulating materials formed adjacent or between conductive electrical components.
A prior art semiconductor wafer fragment 10 is illustrated in FIG. 1. Wafer fragment 10 comprises a substrate 12 and conductive electrical components 14, 16 and 18 overlying substrate 12. Conductive electrical components 14, 16 and 18 may comprise, for example, conductive lines. Such conductive lines may be formed from metal, or conductively-doped polysilicon. Between conductive components 14, 16 and 18 is formed an insulative material 20. Material 20 electrically isolates conductive elements 14, 16 and 18 from one another. Insulative material 20 may comprise materials known to persons of ordinary skill in the art, including, for example, silicon dioxide, silicon nitride, and undoped silicon. Although each of these materials has good insulative properties, the materials disadvantageously have high dielectric constants which can lead to capacitive coupling between proximate conductive elements, such as elements 14, 16 and 18. For instance, silicon nitride has a dielectric constant of about 8 and undoped silicon has a dielectric constant of about 11.8.
A prior art method for insulating conductive elements 14, 16 and 18 from one another, while reducing a dielectric constant of a material between conductive elements 14, 16 and 18 is illustrated in FIGS. 2 and 3. In referring to FIGS. 2 and 3, similar numbers to those utilized in FIG. 1 will be used, with differences indicated by the suffix xe2x80x9caxe2x80x9d or by different numerals.
Referring to FIG. 2, a semiconductor wafer fragment 10a is illustrated. Fragment 10a comprises a substrate 12a, and overlying conductive lines 14a, 16a and 18a. Between lines 14a, 16a and 18a is a carbon layer 22. Conductive lines 14a, 16a and 18a are inlaid within carbon layer 22 by a damascene method. A thin, gas-permeable, silicon dioxide layer 24 is formed over conductive lines 14a, 16a and 18a, and over carbon layer 22.
Referring to FIG. 3, carbon layer 22 is vaporized to form voids 26 between conductive elements 14a, 16a and 18a. Voids 26 contain a gas. Gasses advantageously have dielectric constants of about 1.
It would be desirable to develop alternative methods for insulating conductive elements from one another with low-dielectric-constant materials.
The invention encompasses methods of forming insulating materials between conductive elements. The invention pertains particularly to methods utilizing low-dielectric-constant materials for insulating conductive elements, and to structures encompassing low-dielectric-constant materials adjacent or between conductive elements.
In one aspect, the invention encompasses a method of forming a material adjacent a conductive electrical component. The method includes providing a mass adjacent the conductive electrical component and partially vaporizing the mass to form a matrix adjacent the conductive electrical component. The matrix can have at least one void within it.
In another aspect, the invention encompasses a method of forming a material adjacent a conductive electrical component which includes providing a mass comprising polyimide or photoresist adjacent the conductive electrical component. The method further includes at least partially vaporizing the mass.
In another aspect, the invention encompasses a method of forming a material between a pair of conductive electrical components. The method includes forming at least one support member between the pair of conductive electrical components. The method further includes providing a mass between the at least one support member and each of the pair of conductive electrical components. Additionally, the method includes vaporizing the mass to a degree effective to form at least one void between the support member and each of the pair of conductive electrical components.
In yet another aspect, the invention encompasses an insulating material adjacent a conductive electrical component. The insulating material comprises a matrix and at least one void within the matrix.
In yet another aspect, the invention encompasses an insulating region between a pair of conductive electrical components. The insulating region comprises a support member between the conductive electrical components, the support member not comprising a conductive interconnect. The insulating region further comprises at least one void between the support member and each of the pair of conductive electrical components.